The present invention is directed toward the art of communication systems and, more particularly, to industrial communication and control systems of the type including multiple data and command producer devices connected via diverse media types to multiple data and command consumer devices and will be described with particular reference thereto. However, it is to be appreciated that the present invention finds application in any network system where command, data, or other information is exchanged between a plurality of nodes over a variety of media types.
There are many prior art communication systems that rely on a bus type hardware topology to support fast information transfer between multiple communication modules and repeater devices within an industrial application. Systems of this type are commonly referred to as multi-drop communication systems. Although such multi-drop communication systems using bus type topologies are well suited for efficient communication and data transfer, expanding those systems, once installed, to include additional devices is difficult. In that regard, one problem associated with traditional multi-drop communication networks is that they are expandable only at the outer two ends of the bus. This being the case, it is often impossible to freely add communication devices at locations in the network where they may be most needed, without re-configuring the entire network anew.
Therefore, it is desirable to provide an improved industrial control network, preferably a modular communication repeater system, of the type which makes it easy to exchange, add, and subtract communication modules anywhere within the system as needed without dismantling the network and reconfiguring the system anew.
It is also desirable to provide a communication system that supports not only all standard network topologies such as, for example, bus, star, and ring topologies but one that supports all forms of custom or specialized topologies as well. It would further be desirable to be able to expand the communication network to use additional communication devices as needed and where needed regardless of the network topology.
It is also desirable to provide an industrial modular repeater system of the type that supports multiple media types using multiple technologies such as copper based, fiber based, and broadcast type media, hardware, and methods. A preferred repeater system would be adaptable for use with twisted pair, co-axial cable, IR, RF, glass, plastic, and other media types within a single communication system.
The subject invention provides an improved communication repeater system adapted for use in an industrial control system to repeat communication activity detected on one communication port onto multiple communication ports in the industrial control system. Each communication port is interfaced to a media type that is based on the requirements of the target application. In that way, communication activity detected on one communication media is repeated onto multiple communication media of one or more different types in the industrial control system. The media type is transparent to the repeater system.
The modular communication repeater of the invention includes at least one communication repeater adapter device and a plurality of repeater communication modules connected together in a stacked side-by-side arrangement interengaged with the repeater adapter. A single repeater adapter connector is provided on one side of the repeater adapter. The repeater adapter connector has a first set of repeater adapter contacts at a first position on the connector and a second set of repeater adapter contacts at a second position on the connector. In addition, the repeater adapter device includes an internal communication repeater circuit that operates to receive communication data on a one of the first and second sets of repeater adapter contacts and then immediately re-broadcast the communication data onto the other one of the first and second sets of repeater adapter contacts. The communication activity is re-broadcast substantially simultaneously as it is received.
Each of the plurality of stacked first repeater communication modules includes a set of input and output connectors and a communication circuit for transmitting and receiving communication data on at least one communication port in the industrial control system. The communication ports in the modules support all of the above-identified media types, as needed, based on the media type needs of the application. The output connectors on the communication modules are substantially identical in construction to the repeater adapter output connector. The input connectors on the communication modules are each intermatable with the repeater adapter output connector and, further, are intermatable with the output connectors on each of the other communication modules.
The input connectors on the communication modules have a first set of electrical contacts connected to the first set of repeater adapter output contacts, and a second set of electrical contacts connected to the second set of repeater adapter output contacts. The first output connector on the communication modules includes a first set of electrical contacts arranged on the first output connector at a first position substantially corresponding to the first position of the first set of repeater adapter output contacts on the repeater adapter connector, and a second set of electrical contacts arranged on the first output connector at a second position substantially corresponding to the second position of the second set of repeater adapter output contacts on the repeater adapter connector.
Lastly, each of the plurality of first repeater communication modules includes a first backplane interconnecting the first set of electrical contacts in the first input connector to the first communication circuit in the module. The first backplane also interconnects the second set of electrical contacts in the first input connector to the first set of electrical contacts in the first output connector.
As can be seen from the foregoing, the primary object of the present invention is to provide an improved industrial modular repeater communication system that is easily expandable and adapted to transmit and receive communication data and commands on multiple physical media types within a single network. The architecture of the subject modular repeater communication system is media independent.
It is an advantage of the present invention that the plurality of communication modules connected to a single repeater adapter are adapted to function independently of their respective intermated positions adjacent the repeater adapter unit. Each communication module includes a swizzled backplane connected on either end to a module connector. When the modules are interconnected, the backplane provides for communication of data and commands between the module connectors to the set of intermated modules without the requirement of port or destination identification tags, specialized hardware jumpers, or the like.
It is yet another advantage of the present invention that the plurality of communication modules are adapted to provide a hardware layer interface that is easily adaptable for use with a wide variety of media types including copper based, fiber based, and broadcast type media technologies such as radio frequency or infra-red, as examples.
Still other advantages and benefits of the invention will become apparent to those skilled in the art upon a reading and understanding of the following detailed description.